This seems legal, but upon closer inspection, the form of the sandwich was destroyed. Thus it breaks rule number two, and is subject to the law of rule breaking being non-canon. The universe being destroyed also violates rule number three, so this means even if my logic failed before, this still isn't canon. I retain the sandwich.
And also, an anti-sandwich would destroy the sandwich. We say it can't be created or destroyed, but with anti-matter, i believe it can.